Angolan authorities extended votes in the country's landmark first post-war election into a 2nd day after a chaotic start fuelled opposition demands for new polls.

Angolan authorities extended voting in the country's landmark first post-war election into a second day on Saturday after a chaotic start fuelled opposition demands for new polls.

With President Jose Eduardo dos Santos's ruling MPLA party expected to extend its grip on power in Africa's leading oil-producing nation, 320 polling stations were to reopen because of problems on the first day, the electoral commission said.

Voter material and equipment was not delivered to many stations, especially in Luanda, and the opposition demanded the election be held again.

Most Angolans revelled in the opportunity to vote for the first time since the end of a 27-year civil war in 2002 that claimed 500,000 lives, forming long queues outside polling stations and patiently waiting for hours.

"These elections mean a lot because now people are free. During the war people were not free," said Ana Lopes, voting in one of Luanda's many poor neighbourhoods.

"We have been waiting for 16 years (for this vote) and now we won't have to wait another 16 because elections will happen every four years now," Maria Bernadeth Fransico, a woman in her fifties, said.

A European Union observer mission called the organisation of the vote in Luanda a "disaster".

And before news of the extended voting was announced, the leader of the opposition National Union for the Total Independence of Angola (UNITA), Isaias Samakuva, alleged that the electoral process had "collapsed" and demanded a new vote.

"What we want is the cancellation of this election," added Sindiangani Mbimbi, leader of the Party for Development, Progress and National Alliance of Angola (PDP-ANA).

"For us, this election has been a political theatre... We wanted a credible and peaceful process where all the parties would have equal chances."

While Angola's new wealth stems from its vast oil and diamond riches, fuelling double-digit growth, most of its 17 million people remain mired in poverty, living on less than two dollars a day.

UNITA -- whose guerrillas fought Dos Santos' Popular Movement for the Liberation of Angola -- branded the election as unfair before it began, and accused the MPLA of misusing state funds and resources for campaigning.

Despite confusion in Luanda, home to more than 20 per cent of the eight million registered voters, it appeared the election went more smoothly in the rest of the country.

Dos Santos, 66, said: "It's a very important and historical moment. The most important thing for us is that Angola emerges the winner in this great attempt to consolidate democracy."

Samakuva said: "Some of our delegates have received false credentials, or were given wrong addresses of non-existent polling stations. There is a lot of confusion mainly here in Luanda."

Angola held one attempted election in 1992 -- but UNITA claimed it was fixed, withdrew and new hostilities started.

The electoral commission has 15 days to count the votes. But observers said the first partial results could come as early as Saturday.